Cooling device boiling and condensing refrigerant

1. A cooling device for boiling and condensing refrigerant for cooling a heat-generating member, said cooling device comprising; a refrigerant tank for containing liquid refrigerant, said refrigerant tank having first and second wall surfaces disposed approximately vertically to be opposite to each other, and a boiling space between said first and second wall surfaces, in which a part of liquid refrigerant is boiled and vaporized to gas refrigerant by absorbing heat from the heat-generating member attached onto said first wall surface; a radiator having a first header into which gas refrigerant from said boiling space flows, a plurality of tubes in which gas refrigerant from said first header is cooled and condensed by performing heat exchange with outside fluid passing through said radiator, and a second header through which liquid refrigerant condensed in said tubes returns to said refrigerant tank, wherein: said second wall surface of the refrigerant tank has a first connection portion communicating with said boiling space at a gas refrigerant outlet, and a second connection portion through which said second header communicates with said boiling space; said first header is disposed to extend in a tank longitudinal direction approximately horizontally, and is connected to said first connection portion to be approximately perpendicular to said second wall surface; said second header is connected to said second connection portion to be approximately perpendicular to said second wall surface; said first header has an inserted end portion being inserted into said refrigerant tank from said first connection portion to form a communication port through which an inner space of said first header communicates with said boiling space; said first header has a plurality of tube insertion holes arranged in the tank longitudinal direction, into which said tubes are inserted to protrude inside said first header; and said communication port has a lower end at a position lower than the lower end of said tubes inserted into said first header.

2. The cooling device according to claim 1 , wherein: said tubes are arranged in upper and lower two lines between said first and second headers; and said first header has therein a partition wall for partitioning said tubes on the upper line and said tubes on the lower line within said first header.

3. The cooling device according to claim 1 , wherein said refrigerant tank and said radiator are integrally connected by brazing.

4. The cooling device according to claim 1 , wherein said inserted end portions of said tubes are opened within said first header toward a downstream side in a flow direction of gas refrigerant flowing through said first header.

5. The cooling device according to claim 1 , wherein said first header has therein a protrusion protruding inside from an inner surface of said first header.

6. The cooling device according to claim 5 , wherein said protrusion is formed into a zigzag shape.

7. The cooling device according to claim 5 , wherein said protrusion is disposed to be inclined relative to a flow direction of gas refrigerant flowing through said first header.

8. The cooling device according to claim 5 , wherein said protrusion is disposed to contact said inserted end portions of said tubes at an upstream side of said tubes in a flow direction of gas refrigerant flowing through said first header.

9. The cooling device according to claim 1 , wherein: said tubes are laminated to form a core portion between said first and second headers; said first header has a side wall surface contacting with outside fluid in a flow direction of outside fluid; and said side wall surface is provided in such a manner that outside fluid contacting the side wall surface flows toward said core portion.

10. The cooling device according to claim 9 , wherein said side wall surface protrudes from said core portion and is bent toward said core portion to be inclined relative to the flow direction of outside fluid.

11. The cooling device according to claim 9 , further comprising: a duct for defining a fluid passage through which outside fluid flows toward said core portion, wherein said duct is disposed to enclose said first and second headers along outer wall surfaces of said first and second headers.

12. The cooling device according to claim 9 , further comprising: an inlet pipe for pouring refrigerant into said refrigerant tank, wherein said inlet pipe is disposed on said second wall surface.

13. The cooling device according to claim 12 , wherein said inlet pipe is disposed on an extending line of said first header in a direction parallel to a flow direction of outside fluid.

14. The cooling device according to claim 12 , wherein said inlet pipe is disposed around an extending line of said first header in a direction parallel to a flow direction of outside fluid.

15. The cooling device according to claim 1 , wherein: said tubes are laminated to form a core portion between said first and second headers; said second header has a side wall surface contacting outside fluid in a flow direction of outside fluid; and said side wall surface of said second header is provided in such a manner that outside fluid contacting the side wall surface flows toward said core portion.

16. The cooling device according to claim 9 , wherein: said first header has an inner plate connected to tubes, and an outer plate opposite to said inner plate and being connected to said inner plate; said inner plate is connected to said core portion to form said side wall surface contacting outside fluid in the flow direction of outside fluid; and said outside plate has a flat outer wall surface.

17. The cooling device according to claim 1 , wherein the first header has an inner bottom surface lower than the lower end of the communication port.

18. A cooling device for boiling and condensing refrigerant for cooling a heat-generating member, said cooling device comprising: a refrigerant tank for containing liquid refrigerant, said refrigerant tank having first and second wall surfaces disposed approximately vertically to be opposite each other and a boiling space between said first and second wall surfaces in which a part of liquid refrigerant is boiled and vaporized to gas refrigerant by absorbing heat from the heat generating member attached to said first wall surfaces; a radiator having a first header into which gas refrigerant from said boiling space flows, a plurality of tubes in which gas refrigerant from said first header is cooled and condensed by performing heat exchange with outside fluid passing through said radiator, and a second header through which liquid refrigerant condensed in said tubes returns to said refrigerant tank; wherein: said first header communicates with said boiling space through a gas refrigerant outlet defined by said second wall surface; each of said plurality of tubes defining a bore having its lowest end open at a position above said gas refrigerant outlet within said first header such that all liquid refrigerant within said bore of each of said tubes flows into one of said first and second headers.